This program, which has as its aim elucidation of mechanisms of hormone action at the molecular level, is being forwarded in several close-related areas: analysis of proximate interactions of hormones, both steroid and peptidal, at the outer surfaces of specific target cells; analysis of the secondary effects of such interactions and their immediate consequences in membrane perturbation and internalization; analyses of the lysosome-mediated transfer of signals arising from the above to other cellular compartments, including the cytoplasm and the nucleus; analyses of the contributions of recompartmentalized components of hormone-activated lysosomes upon subsequent transcriptional and translational events.